When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
650cm3 is the same as 650cc and that is the same as 650ml which will be usually marked on the side of the oil container. there is 946ml in one quart so about 7/10ths of a quart will be close enough if it is not marked.